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Metals are found to the [...] of the BAt line in the periodic table (the diagonal line from B to At).

Metals are found to the left of the BAt line in the periodic table (the diagonal line from B to At).

Although pennies were originally made of copper, they are now made of copper-plated zinc. Because that much copper would be [...].

Although pennies were originally made of copper, they are now made of copper-plated zinc. Because that much copper would be worth much more than a penny.

There are three different, major groups of metals on the periodic table: alkali metals, [...] metals, and transition metals.

There are three different, major groups of metals on the periodic table: alkali metals, alkaline earth metals, and transition metals.

There are three different, major groups of metals on the periodic table: alkali metals, alkaline earth metals, and [...] metals.

There are three different, major groups of metals on the periodic table: alkali metals, alkaline earth metals, and transition metals.

All money in the United States was once backed up by actual gold and silver held by the US Treasury. This meant that the government could not print more money than it had gold or silver. This is known as the [...].

All money in the United States was once backed up by actual gold and silver held by the US Treasury. This meant that the government could not print more money than it had gold or silver. This is known as the gold standard.

Bronze is a mixture of copper and [...]. The Bronze age refers to a time when bronze was the hardest known metal and thus, weapons were made of bronze.

Bronze is a mixture of copper and tin. The Bronze age refers to a time when bronze was the hardest known metal and thus, weapons were made of bronze.

Brass is a mixture of copper and [...]. Brass is easy shape (like gold), so it's used in a lot of musical instruments and decorations.

Brass is a mixture of copper and zinc. Brass is easy shape (like gold), so it's used in a lot of musical instruments and decorations.

Steel is a mixture of iron and [...]. In the old days, blacksmiths discovered that adding a small amount of coal to iron made a much stronger material.

Steel is a mixture of iron and carbon. In the old days, blacksmiths discovered that adding a small amount of coal to iron made a much stronger material.